Bug ID 701186: With auto-lasthop enabled tmm accepts traffic from invalid addresses

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
12.1.2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 12.1.5.1, 12.1.5.2, 12.1.5.3, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 13.1.3.5, 13.1.3.6, 13.1.4, 13.1.4.1, 13.1.5, 13.1.5.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1

Fixed In:
14.1.0

Opened: Jan 09, 2018

Severity: 3-Major

Symptoms

Tmm accepts traffic from incorrect source addresses: - 127.0.0.0/8 - 0.0.0.0/8

Impact

RFC6890 violation. Note: This is not a vulnerability, as traffic is getting returned to the lasthop populated via auto-lasthop. Therefore, no traffic is reaching the host; it is only an RFC violation.

Conditions

Auto-lasthop enabled.

Workaround

To mitigate this issue, use the following packet filter: net packet-filter /Common/drop_local { action discard order 5 rule "( src net 0.0.0.0/8 or src net 127.0.0.0/8 )" }

Fix Information

TMM drops traffic from incorrect source addresses: - 127.0.0.0/8 - 0.0.0.0/8

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips